Gov. Jerry Brown has signed a Bay Area lawmaker’s bill to curtail wrongful criminal convictions.

SB 687, by state Sen. Mark Leno, D-San Francisco, ensures no California judge or jury convicts a defendant, or approves an aggravating factor in a crime that allows for a stricter penalty, based solely a jailhouse informant’s uncorroborated testimony.

Leno issued a statement saying he’s pleased to see the bill signed into law.

“We know that when used properly, jailhouse informants can be a good investigative tool for prosecutors, but they can also be destructive, crime-producing and corrupting,” Leno said. “SB 687 ensures that in-custody informant testimony is supported by corroborating evidence that connects the accused with the crime that was committed. Without the safeguards created in this legislation, the potential for the miscarriage of justice when informant testimony is involved is just too high.”

The bipartisan California Commission on the Fair Administration of Justice recommended this in 2006 as a means of avoiding wrongful convictions; it was supported by the San Francisco and Los Angeles district attorneys, among others, but the California District Attorneys Association opposed it. Gov. Arnold Schwarzenegger vetoed similar bills. The state Senate passed it in May on a 23-15 vote, and the Assembly passed it in July on a 47-26 vote.